1. Field of the Invention
This invention relates to novel perfluorocarboxylic acid fluorides, nitrogen-containing perfluoropropenes, and a method for the production of these compounds. More particularly, this invention relates to perfluoro(dialkylaminobutyryl fluorides) and perfluoro(dialkylaminopropenes) which are useful intermediates for the manufacture of fluorine-containing products such as surfactants, agricultural pesticides, and medicines and for the synthesis of fluorine-containing macromolecular monomers and to a method for efficient production of these compounds from readily available raw materials.
2. Prior Art Statement
In recent years, fluorine-containing compounds of various kinds have been developed. For example, perfluorocarboxylic acid fluorides such as perfluorocaprylyl fluoride and olefin compounds such as perfluoroolefins containing a perfluoro(N,N-dialkyl)amino group (described more fully later) have found extensive utility as intermediates for the synthesis of surfactants, dyes, agricultural pesticides, and medicines and as monomers for the manufacture of fluorine-containing macromolecular compounds, for example.
The perfluorocarboxylic acid fluorides mentioned above have been heretofore produced mainly by the electrolytic fluorination method. Beside this method, a method employing the reaction of R.sub.f I with SO.sub.3 or with ClSO.sub.3 H (French Pat. No. 1,343,661 and U.S. Pat. No. 3,238,240) and a method employing the oxidation of R.sub.f CH.dbd.CCl.sub.2 (Japanese Patent Public Disclosure SHO 60(1985)-188345) (wherein R.sub.f stands for a perfluoroalkyl group) are known to the art.
The only perfluorocarboxylic acid fluorides containing a nitrogen atom as a hetero atom known to the art are, perfluoro(N,N-dimethylaminoacetyl fluoride) ["Journal of American Chemical Society", vol. 80, page 1,889 (1959)], perfluoro (.beta.-alkylaminopropionyl fluorides) (U.S. Pat. No. 3,471,484), and perfluoro(.alpha.-alkylaminopropionyl fluorides) (Japanese Patent Applications SHO 60(1985)-103042 and SHO 60(1985)-166,888). No other long-chain carboxylic acid fluoride containing a perfluorodialkylamino group are known to exist.
Fluorine-containing olefin compounds will now be described. For example, perfluoroolefins containing a perfluoro(N,N-dialkyl)amino group possess a double bond as a portion for reaction. By using these compounds as an intermediate raw material, therefore, various useful compounds possessing the perfluoro(N,N-dialkylamino) group can be produced. When these perfluoroolefins are copolymerized with other fluoroolefins to effect incorporation of the perfluoro(N,N-dialkylamino) group in the products of the copolymerization, the produced copolymers enjoy improvements in crystallinity and mechanical properties.
As the perfluoroolefins described above, perfluoro(N-vinylamines) such as perfluoro(N,N-dimethylvinylamines) (U.S. Pat. No. 3,311,599), perfluoro(N-vinylpyrrolidines) (Japanese Patent JP 62-22755(1987)), perfluoro(N-vinylmorpholines) ["Journal of Chemical Society", Perkin I, page 5 (1973)], and perfluoro(N-vinylpiperidine) ["Journal of Chemical Society", (C) page 2,608 (1968)] and perfluoro[3-(N,N-dimethylamino)-2-propene] ["Journal of Chemical Society", Perkin I, page 1,633 (1975)] are currently known. Among these perfluoroolefins, perfluoro[3-(N,N-dimethylamino)-2-propene], which is the only known perfluoro[(N,N-dialkyl)propenylamine], is synthesized by a two-step reaction methodologically, i.e. (1) first causing radical addition reaction of N-bromobistrifluoromethylamine with 1H-pentafluoropropene-1 thereby obtaining a 1:1 adduct and (2) then subjecting the 1:1 adduct to a dehydrogen bromide reaction thereby forming an unsaturated bond in the reaction product.
To be specific, the two-step reaction is represented by reaction formulas as follows. ##STR3##
This method, however, has an inherent defect in that it is incapable of synthesizing (CF.sub.3).sub.2 NCF.sub.2 CF.dbd.CF.sub.2 as a terminal olefin. Further, the synthesis of(CF.sub.3).sub.2 NBr and CH.sub.3 CF.sub.2 .dbd.CHF as raw materials requires many complicated treatment steps. Since this method necessitates the two-step key reaction mentioned above, it has another disadvantage in that it is complicated operationally. When this method is applied to the synthesis of another kind of perfluoroalkenylamine, ##STR4## the synthesis of a perfluoroalkylamino radical donor, ##STR5## wherein X is Cl, Br, or F), indispensable to the synthesis of the 1:1 adduct as a precursor, is difficult. Thus, this method has a disadvantage in that it cannot be easily utilized for general purposes.